A question about water change

[pettygil]

I have a 40 tall tank. I added 9 gallon jugs to the water. Is that too big of water change, or do less wc? My bigger tank water quality is fine. it's my 6.5 gallon tank I struggle with.

 

[Aiken Drum]

A 40 gallon tank is probably going to have 35 gallons of water in it, when you account for substrate, aquascape etc. So 9 gallon water change is going to be about a 25% water change. Most people generally change 30 to 50% when doing a water change.

Your water change schedule can largely be dictated by your nitrate levels. If nitrate is less than 40ppm before your regular water change thats OK. If its less than 20ppm thats great. If its more than 40ppm you either need to increase your water change schedule, reduce the number of fish, or get a bigger tank.

 

[Andy Sager]

What Aiken said.
The amount you change is determined by the quality of your water before you change it. You change water for more reasons than just to reduce nitrates so changing any water is going to replenish minerals in the water that the fish have absorbed out. The more fish you have in the tank, the more water you should be changing.

 

[pettygil]

My nitrates were fine

A 40 gallon tank is probably going to have 35 gallons of water in it, when you account for substrate, aquascape etc. So 9 gallon water change is going to be about a 25% water change. Most people generally change 30 to 50% when doing a water change.

Your water change schedule can largely be dictated by your nitrate levels. If nitrate is less than 40ppm before your regular water change thats OK. If its less than 20ppm thats great. If its more than 40ppm you either need to increase your water change schedule, reduce the number of fish, or get a bigger tank.

My nitrates were fine. I went almost a month before a WC, so I figure I better do a WC. I use the liquid test kits to see about ammonia and that was fine as well. Next time I will do 12 gallons of water. That should be about 30 percent at least I think it is. If not then let me know.

 

[pettygil]

my water quality is fine

What Aiken said.
The amount you change is determined by the quality of your water before you change it. You change water for more reasons than just to reduce nitrates so changing any water is going to replenish minerals in the water that the fish have absorbed out. The more fish you have in the tank, the more water you should be changing.

My water quality is fine, but it was getting close to a month, so i did a water change.

 

[Aiken Drum]

My nitrates were fine. I went almost a month before a WC, so I figure I better do a WC. I use the liquid test kits to see about ammonia and that was fine as well. Next time I will do 12 gallons of water. That should be about 30 percent at least I think it is. If not then let me know.

If your water quality is fine after a month of no water changes then i wouldnt say you need to do bigger water changes. That 25% is fine, maybe just do that every 2 weeks instead of monthly.

 

[pettygil]

ok well do

If your water quality is fine after a month of no water changes then i wouldnt say you need to do bigger water changes. That 25% is fine, maybe just do that every 2 weeks instead of monthly.

ok well do WC every two weeks at 25 percent. Now If I could get my 6.5 gallon tanks to once a week, the fish would have it made in the shade. The bigger the tank the better. i do not think I need a 10 gallon tank for one betta, that be like super manson for betta all by him self.

 

[angiemike6]

I also have a 40 gallon tank, and I do 25% every week. My tank is overstocked but doing the weekly water changes keeps my nitrate level around 20 ppm.

 

[Andy Sager]

My water quality is fine, but it was getting close to a month, so i did a water change.

It's good that you were able to go that long without having a high nitrate level but as I've said before, we change water for more reasons than just to control nitrate levels. It's not a bad idea to keep to at least a 2 week schedule so that you are consistently replenishing minerals and elements in the water for the fish. This fish will show how much they like that.